This is another of those spec interpretation questions. Sorry to populate this list with so many of these questions but this is a source of real irritation for me in the moment. I just want to get sub/superscripts working and do it properly and I am hitting all these "murky" (as Peter put it) things in the spec.
Here we go again. In 7.13 the spec defines the various baselines. In that section it says: "There are, in addition, two computed baselines that are only defined for line areas." and then goes on about those two baselines being "before-edge" and "after-edge". We then come to 7.13.1 alignment-adjust and "before-edge" and "after-edge" are valid values. However, the alignment-adjust property applies only to inline fo's. And inline fo's don't generate line areas. As the alignment-adjust property applies to the area generated by the fo (not like the alignment-baseline property which applies to the parent area) none of the areas generated by the fo's in question will have those baselines defined. The text also implies that i-f-o and and e-g have the "after-edge" as their dominant baseline. For the "auto" setting we are allowed to use heuristics to determine where the baseline is but that option is not open to the other values. So, what's the point of having "before-edge", "after-edge" as allowed values if those baselines are guaranteed not to be defined (and even use them as default for e-g and i-f-o)? Manuel
